matchit/
error.rs

1use crate::tree::{denormalize_params, Node};
2
3use std::fmt;
4
5/// Represents errors that can occur when inserting a new route.
6#[non_exhaustive]
7#[derive(Clone, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
8pub enum InsertError {
9    /// Attempted to insert a path that conflicts with an existing route.
10    Conflict {
11        /// The existing route that the insertion is conflicting with.
12        with: String,
13    },
14    /// Only one parameter per route segment is allowed.
15    TooManyParams,
16    /// Parameters must be registered with a name.
17    UnnamedParam,
18    /// Catch-all parameters are only allowed at the end of a path.
19    InvalidCatchAll,
20}
21
22impl fmt::Display for InsertError {
23    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
24        match self {
25            Self::Conflict { with } => {
26                write!(
27                    f,
28                    "insertion failed due to conflict with previously registered route: {}",
29                    with
30                )
31            }
32            Self::TooManyParams => write!(f, "only one parameter is allowed per path segment"),
33            Self::UnnamedParam => write!(f, "parameters must be registered with a name"),
34            Self::InvalidCatchAll => write!(
35                f,
36                "catch-all parameters are only allowed at the end of a route"
37            ),
38        }
39    }
40}
41
42impl std::error::Error for InsertError {}
43
44impl InsertError {
45    pub(crate) fn conflict<T>(route: &[u8], prefix: &[u8], current: &Node<T>) -> Self {
46        let mut route = route[..route.len() - prefix.len()].to_owned();
47
48        if !route.ends_with(&current.prefix) {
49            route.extend_from_slice(&current.prefix);
50        }
51
52        let mut last = current;
53        while let Some(node) = last.children.first() {
54            last = node;
55        }
56
57        let mut current = current.children.first();
58        while let Some(node) = current {
59            route.extend_from_slice(&node.prefix);
60            current = node.children.first();
61        }
62
63        denormalize_params(&mut route, &last.param_remapping);
64
65        InsertError::Conflict {
66            with: String::from_utf8(route).unwrap(),
67        }
68    }
69}
70
71/// A failed match attempt.
72///
73/// ```
74/// use matchit::{MatchError, Router};
75/// # fn main() -> Result<(), Box<dyn std::error::Error>> {
76/// let mut router = Router::new();
77/// router.insert("/home", "Welcome!")?;
78/// router.insert("/blog/", "Our blog.")?;
79///
80/// // a route exists without the trailing slash
81/// if let Err(err) = router.at("/home/") {
82///     assert_eq!(err, MatchError::ExtraTrailingSlash);
83/// }
84///
85/// // a route exists with a trailing slash
86/// if let Err(err) = router.at("/blog") {
87///     assert_eq!(err, MatchError::MissingTrailingSlash);
88/// }
89///
90/// // no routes match
91/// if let Err(err) = router.at("/foobar") {
92///     assert_eq!(err, MatchError::NotFound);
93/// }
94/// # Ok(())
95/// # }
96#[derive(Debug, PartialEq, Eq, Clone, Copy)]
97pub enum MatchError {
98    /// The path was missing a trailing slash.
99    MissingTrailingSlash,
100    /// The path had an extra trailing slash.
101    ExtraTrailingSlash,
102    /// No matching route was found.
103    NotFound,
104}
105
106impl MatchError {
107    pub(crate) fn unsure(full_path: &[u8]) -> Self {
108        if full_path[full_path.len() - 1] == b'/' {
109            MatchError::ExtraTrailingSlash
110        } else {
111            MatchError::MissingTrailingSlash
112        }
113    }
114}
115
116impl fmt::Display for MatchError {
117    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
118        let msg = match self {
119            MatchError::MissingTrailingSlash => "match error: expected trailing slash",
120            MatchError::ExtraTrailingSlash => "match error: found extra trailing slash",
121            MatchError::NotFound => "match error: route not found",
122        };
123
124        write!(f, "{}", msg)
125    }
126}
127
128impl std::error::Error for MatchError {}
matchit/error.rs

matchit/
error.rs
